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The Problem
My SE Linux Play Machine has been down for a couple of weeks. I’ve changed to a cheaper Internet access plan which also allows me to download a lot more data, but I don’t have a static IP address any more – and my ISP seems to change the IP a lot more often than I’ve experienced in the past (I’m used to having a non-static IP address not change for months rather than hours). So I needed to get Dynamic DNS working. Naturally I wasn’t going to use one of the free or commercial Dynamic DNS solutions, I prefer to do things myself. So my Play Machine had to remain offline until I fixed this.
The Solution
dyn IN NS ns.sws.net.au.
IN NS othello.dycom.com.au.
play IN CNAME play.dyn.coker.com.au.
The first thing I did was to create a separate zone file, I put the above records in my main zone file to make play.coker.com.au be a CNAME for play. and dyn.coker.com.au is a dynamic domain. I have SE Linux denying BIND the ability to write to the primary zone file for my domain to make it slightly more difficult for an attacker to insert fake DNS records (they could of course change the memory state of BIND to make it serve bogus data). The dynamic zone file is stored where BIND can write it – and therefore a BIND exploit could easily replace it (but such an attack is out of the scope of the Play Machine project so don’t get any ideas).
Another reason for separating the dynamic data is that BIND journals changes to a dynamic zone and therefore if you want to manually edit it you have to delete the journal, stop BIND, edit the file, and then restart BIND. One of the things that interests me is setting up dynamic DNS for some of my clients, as a constraint is that my client must be able to edit the zone file themself I have to keep the editing process for the main zone file relatively simple.
dnssec-keygen -a hmac-md5 -b 128 -n host foo-dyn.key
For newer versions of BIND use the following command instead:
tsig-keygen -a hmac-sha512 foo-dyn
I used the above command to create the key files. It created Kfoo-dyn.key.+X+Y.key and Kfoo-dyn.key.+X+Y.private where X and Y are replacements for numbers that might be secret.
key "foo" { algorithm hmac-md5; secret "XXXXXXXX"; };
zone "dyn.coker.com.au" {
type master;
file "/var/cache/bind/dyn.coker.com.au";
allow-update { key "foo"; };
allow-transfer { key ns; };
};
I added the above to the BIND configuration to create the dynamic zone and allow it to be updated by this key. The value which I replaced with XXXXXXX in this example came from Kfoo-dyn.key.+X+Y.key. I haven’t found any use for the .private file in this mode of operation. Please let me know if I missed something.
Finally I used the following shell script to take the IP address from the interface that is specified on the command-line and update the DNS with it. I chose a 120 second timeout because i will sometimes change IP address often and because the system doesn’t get enough hits for anyone to care about DNS caching.
#!/bin/bash
set -e
IP=$(ip addr list $1|sed -n -e "s/\/.*$//" -e "s/^.*inet //p")
nsupdate -y foo:XXXXXXXX << END
update delete play.dyn.coker.com.au A
update add play.dyn.coker.com.au 120 A $IP
send
END
Update
It is supposed to be possible to use the -k option to nsupdate to specify a file containing the key. Joey’s comment gives some information on how to get it working (it sounds like it’s buggy).
rhesa pointed out another way of doing it, so I’ve now got a script like the following in production which solves the security issue (as long as the script is mode 0700) and avoids using other files.
#!/bin/bash
set -e
IP=$(ip addr list $1|sed -n -e "s/\/.*$//" -e "s/^.*inet //p")
nsupdate << END
key foo XXXXXXXX
update delete play.dyn.coker.com.au A
update add play.dyn.coker.com.au 120 A $IP
send
END
Update
Added a reference to the tsig-keygen command for newer bind.
LWN has a recent article titled “The dark side of open source conferences” which concerns sexual assault at conferences [1].
There are a significant number of comments with attempts to derail the discussion in ways that can really only be interpreted as attacks on Autistic people. The claims seem to be that the problem is not violent sexual assault at conferences, but guys on the Autism Spectrum who hit on girls when they don’t want it. Naturally no supporting evidence was made for such claims. But that doesn’t stop the discussion which has a logical end-point of excluding people like me from conferences.
The Irony
I think it’s ironic that those who are making claims about what they call “empathy disorders” have failed to be Empathic by not realising the following things:
- Women who start a discussion about serious sexual assault probably aren’t going to be happy if someone starts talking about chat-up attempts. While unwanted chat-up attempts are unpleasant they are in a different category and mixing them seems to be diminishing the significance of violent attack.
- Most members of a minority group (in this case women in the Free Software community) probably don’t want discussions of how to help their group diverted by discussions that attack another minority group. What looks a lot like a “divide and conquer” attack against minority groups isn’t going to be appreciated by members of either group – and probably members of other minority groups who see what’s happening aren’t going to like it.
- There is no reason why people should require significant exposure to members of a minority group to treat them in a decent manner. The claim that we need more women at conferences so that men can get used to them and not treat them badly is ridiculous. Among the many stupid aspects of that idea is forgetting the fact that women comprise 52% of the population in first-world countries and we all deal with women every day. Women at IT conferences are not fundamentally different from women in the rest of society.
- When most people interpret your writing in a way other than what you intended it seems to be a reasonable assumption that you failed to explain things clearly. Telling everyone who disagrees to “get therapy” is unlikely to help convey your point. Telling people to “get therapy” is particularly likely to get a bad reaction if you are discussing something that actually involves dealing with psychologists.
- When there is an obvious resource on the Internet relating to a topic it’s a good idea to read it instead of just making stuff up. Failing to do so will be taken as an indication that you aren’t trying to be Empathic. The Wikipedia section on Autism Spectrum Disorders has a lot of useful information [2]. Please read it before making comments about Autism and Empathy.
- Having to be told how other people feel is not inherently a sign of a lack of Empathy. Asking people how they feel because you can’t work it out is a sign of Empathy as it indicates an acknowledgement that other people have different emotions and you probably don’t understand them all. The people who know that they can’t understand other people and listen when told are probably better than average when it comes to Empathy.
- Finally what people say about themselves and their own experiences should be taken seriously.
Some Final Points
Instead of talking about how some other people should be more Empathic it seems that a better idea would be to try and demonstrate Empathy. Set a positive example.
I did a Google search for “Empathy Disorder” and found this interesting article [3]. It’s about how Neuro-Typical people (people who aren’t on the Autism Spectrum) can learn to be more Empathic, it’s probably more relevant to the issue of Empathy in the free software community than discussions of Autism.
I think that the experience of a lot of people on the Autism Spectrum is similar to mine. It’s not that we can’t work things out it’s just that it takes a lot longer. For things that can’t be worked out in real time we have rules based on past experience. Naturally the rules include “don’t touch people” and “don’t try to chat up women at conferences“.
Here is a link to my previous post on this topic [4].
Update: I’ve clarified some of the writing and added an extra point about having to be told how others feel.
LWN has an article by Valerie Aurora titled “The dark side of open source conferences” [1] which is about sexual harassment and sexual assault at Free Software conferences. Apparently some conferences create such a bad environment that some people won’t attend, it’s a well researched article that everyone in the community should read.
The Autism Derailment
The comments have the usual mix of insight, foolishness, and derailment that you expect from such discussions. One derailment thread that annoyed me is the discussion about men on the Autism Spectrum started by Joe Buck [2]. Joe seems to believe that the 1% of males on the Autism Spectrum (and something greater than 1% but a lot less than 50% in the Free Software community) are a serious part of the problem because they supposedly hit on women who aren’t interested in them – in spite of the fact that the article in question is about women who are “being insulted, harassed, and groped at at open source conferences“. The article had no mention of men who try to chat up women – presumably this was a deliberate decision to focus on sexual assault and harassment rather than what Joe wanted to talk about.
In response Mackenzie made the following insightful point:
I don’t think any autistic person who is high-functioning enough to A) contribute to open source B) want to be at an event with so many people and C) carry on any sort of conversation is low-functioning enough not to understand “stop” or “no.” If you can understand “your patch has been rejected,” you can likely understand “don’t do that again.”
Understanding how Other People Feel
Bruce Perens claimed “What they [Aspies] don’t understand is how the other person in the situation feels“. Like many (possibly most) people Bruce doesn’t seem to get the fact that no-one can really understand how other people feel. The best logical analysis of this seems to be the Changing Emotions article on Less Wrong [3]. While Less Wrong deals with Male to Female conversion as the example (which may be relevant to the discussion about the treatment of women) the same logic also applies to smaller changes. Anyone who even thinks that if they would always be able understand how their identical twin felt (if they had one) probably hasn’t considered these issues much. As an aside, having a psychologist diagnose you as being on the Autism Spectrum and therefore by implication thinking differently to 99% of the population really makes you consider the ways in which other people might have different thought processes and experiences.
Every time we have a discussion about issues related to sexism in the Free Software community we get a lot of documented evidence that there are many people who are apparently neuro-typical (IE not Autistic) who don’t understand how other people think – in many cases they go so far as to tell other people what their emotional state should be.
What Really Happens
Nix said “However, in that situation our natural reflex is to *get out of there*, not to jump on women like some sort of slobbering caveman” which is a really good summary.
In more detail, I think that the vast majority of guys who are on the Autism Spectrum and who are able to do things like attend computer conferences (*) realise that chatting up a random girl that they meet is something that just isn’t going to work out. Generally people don’t attempt things that they expect to fail so I don’t think that Autistic guys are going to be hitting on girls at conferences.
(*) Having never met any Autistic people who aren’t capable of attending such conferences I can’t speak for them. I really doubt that the Low Functioning Autistic guys are as much of a problem as some people claim, but lack evidence. In any case the actions of people who don’t attend conferences aren’t relevant to a discussion about things that happen at conferences.
Update: It Keeps Going
Dion claims that the misogyny at conferences is due to socially inept people, he also casually switches between discussing people who misunderstand when someone is flirting and people who hire almost-naked booth-babes (two very different classes of action) [4]. Several people asked for supporting evidence, naturally none was provided.
In response njs posted a link to Marissa Lingen’s blog post “Don’t blame autism, dammit” [5]. Marissa points out that people who offend other people due to lacking social skills will tend to do so in times and places that are likely to get a bad reaction – if you don’t know that you are doing something wrong then there’s no reason to hide it. If someone offends a senior manager at a corporate event then it could be because they are on the Autism Spectrum (I’ve apparently done that). If someone offends junior people at a times and places where there are no witnesses but is always nice to managers and other powerful people then it’s not related to Autism.
One final note, I have little tolerance for anyone who claims to be an Aspie when they do something wrong. You are either on the Autism Spectrum all the time or none of it. Anyone who wants any sympathy for me for an occasion where they stuffed up due to being an Aspie can start by making a clear statement about where they are on the Autism Spectrum.
Update2: Yet More from Bruce Perens
Bruce wrote “IMO, the kind of men who go in to software engineering suffer a lack of healthy interaction with women who are their peers, and it may be that the high incidence of empathy disorders in our field is involved” (which seems to be part of the inspiration for Joe Buck later in that thread) and now claims “Nobody here was trying to connect Asperger’s or autism with the touching incidents or violent crime“.
Matthew Garrett responded to that with “If you weren’t trying to say that the high incidence of empathy disorders in our field was related to a lack of healthy interaction with women who are their peers, and that that has something to do with incidents of sexual harassment or assault at conferences, what were you trying to say? Because that sounds awfully like ‘We wouldn’t have so many problems if it weren’t for all the autists’“.
Bruce’s latest comment is “If you choose to read something that nasty into my writing, that’s your problem. Get therapy“.
Through this discussion I’ve been unsure of whether to interpret the statements by Bruce et al the way Matthew does or whether I should consider them as merely a desperate attempt to derail the discussion. I can’t imagine any possible way of interpreting such comments in connection with the discussion of sexual assault as anything other than either trivialising violent crimes against women (suggesting that they are no worse than asking out someone who’s not interested) or claiming that anyone who lacks social skills should be treated as a violent sexual predator. It’s just not reasonable to believe that every single person who wrote such comments referring to Autism was misunderstood and really meant something nice.
As a general rule I don’t think that it’s the responsibility of other people to try and find a non-offensive interpretation of something that one might say. I don’t think that all the people who strongly disagree with the most obvious and reasonable interpretations of Bruce’s comments should get therapy. I think that Bruce should explain what he means clearly.
Paul Wayper has written a blog post criticising the main chains of grocery stores in Australia [1]. That is the cartel of Coles and Woolworths (which was formerly known as Safeway in some parts of Australia), and the German newcomer Aldi.
While he does make some good points I think he was a little harsh on Aldi. As a portion of the stock on shelves (by quantity stocked, shelf space, number of products, or almost any other metric) it seems that Aldi easily beats every other decent sized grocery chain for the portion of the stock being organic food. Aldi also has a very high portion of their stock being fair-trade – also probably beating the other chains handily. Having organic fair-trade food sold in bulk at low prices is a really good thing!
Paul criticises the lack of range on offer in the major chains. Aldi has the smallest range as their entire business model is based around offering a small range of products in a relatively small store at very low prices. That dramatically decreases the amount of stock that they have and therefore decreases the amount that is spoiled and the expense of storing and tracking it all. I wonder if the success of Aldi can drive other stores to getting a better range of products. Why buy a small range of products from Coles or Woolworths when you can get a similar small range from Aldi at low prices that the business models of Coles and Woolworths can’t match? This may even drive consumers to buying core products (bread, milk, pasta, etc) and some basic luxury products (cooking wine, basic chocolate, cheap soda, etc) from Aldi and then buying other products from specialist stores. This might result in more delicatessens!
Aldi also has a weekly selection of special items. For example selling snow boots etc just before winter starts. In most parts of Australia we don’t see snow much and a cheap pair of snow boots is a good investment for the one day a year that most people spend at the snow. These specials provide real benefits to consumers – although not to the Australian economy.
Paul complains about own brand products. But for some products such as sugar you will get the same product from home brand as from other brands (there aren’t really many options for sugar) and it’ll probably end up being Australian just due to economics.
When you buy big-name products you are mostly paying for marketing. For some things there are real taste differences (such as Coke for me), but for lots of things there are no difference, so I’m happy to buy “own brand”. Generally not paying for marketing is a good thing.
I totally agree with Paul’s point about buying Australian to help the local economy and also to avoid the transmission of diseases. Any treaty which forces us to accept the import of products from countries that have diseases that can be transmitted to Australian crops should be voided. It seems that the WTO is specifically designed to benefit corporations at the expense of member countries and their citizens.
Paul gave a positive review to IGA, I wasn’t impressed with my local IGA the last time I visited it. But I’ll give it another go.
On the 5th of November Jono Bacon wrote a blog post titled “MAKING OUR WORLD MORE RESPECTFUL” [1]. He then registered the domain OpenRespect.org for his manifesto [2].
Aaron Siego supports the general concept of being more respectful while listing some of the practical problems that occur in a multi-cultural world [3]. If you read nothing else about this issue I recommend reading Aaron’s post (which I summarised very poorly, I can’t think of a good one-sentence explanation).
Sam Varghese wrote an article suggesting that it was an attempt to deflect criticism from Ubuntu [4]. I think that Ubuntu receives a lot of unfair criticism, but don’t think it’s really relevant to the issue at hand. Sam criticises some of the Open Respect supporters for failing to show respect in the past.
Jono wrote a follow-up blog post titled “REFLECTIONS ON RESPECT” [5], in that post he said “Sometimes we were disrespectful, and frankly, sometimes we were also inadvertently assholes. We never set out to be assholes, but we did set out to be edgy in a satirical way, but we sometimes went too far and I apologize for that. But you know what, we all grow and mature in different parts of our lives” about his past LugRadio work. Maybe instead of focusing on being respectful of others it would give more benefit to focus on how to apologise, back down, and move on after being disrespectful. It seems that the situations of epic disrespect tend not to be one-off incidents but are instead arguments of greatly expanded scope that arose from someone refusing to admit any error after doing something that is considered to be offensive. [Someone has registered OpenApology.org, just in case you were wondering.]
Maybe advocating Rogerian Argument would be another way of reducing some of the problems in the community.
Finally Kirrily wrote an insightful post about the ineffectiveness of discussing “offensive” things [6]. In terms of issues such as Feminism (which Kirrily uses as an example and which is also a matter of significant interest for her) discussions about “offense” apparently tend to end up being about the person who was offended rather than the person who might be described as acting in an offensive manner. She suggests using terms such as “marginalised, belittled, stereotyped, frustrated, humiliated, threatened, patronised, silenced, intimidated, misrepresented, etc” instead. It seems to me that there may be a similar issue with “respect”. Objective claims about people being dismissed, ignored, patronised, etc can be evaluated more easily than a claim about being disrespected.
The discussion in the comments on my post about a mobile phone for Sysadmin use [1] turned to the issue of picture quality. This is an issue for a sysadmin as photographing the screen of a crashed computer while being a rare occurrence can be an important part of solving a computer problem.
Lon recommended a review of phone cameras by the Norwegian site Amobil [2]. This review only included devices that had already passed earlier review, so even the HTC Desire HD (which came last on the Amobil tests) still has a better camera than most phones on the market. It’s a pity that no English-language site seems to have done such a review.
The Amobil article (when translated) says: “In the mobile industry is faced with the need for much extra processing for the images to look good, because there is no room for large optics and large image sensors that receive sufficient amount of lightâ€.
IMHO that’s overstating the case. I have yet to see a camera-phone that couldn’t be redesigned in a trivial way to give a better camera functionality. It appears that the limiting factor is the thickness of phone which limits the maximum focal length and therefore the maximum area (I presume it’s safe to assume that Fresnel lenses are not viable for cameras). My LG U990 Viewty is 14.8mm thick, I would be happy with something a bit thicker if it gave a better picture, 30mm wouldn’t be a problem (my first few mobile phones were thicker than that and had no camera). Maybe a design could have the camera stick out such that the main body of the phone was 15mm thick while the camera part was 30mm. Also having the camera in a central part of the phone (underneath the touch-screen) probably loses at least 1mm of focal length. It seems that the amount of light captured will be the square of the focal length, so an ideal (IMHO) camera design could have twice the depth of a Viewty, 4* the light captured, and therefore have an 8MP camera with a better response in adverse light than the Viewty (which is pretty good for a phone but crap for a camera).
I noted in the comments that it’s a pity that camera-phones don’t support storing pictures in RAW format, Paul pointed out that the Nokia N900 supports RAW pictures. I’m glad to learn that at least one phone-camera manufacturer is doing the sane thing, now we just need to have RAW pictures as a check-list item on reviews to force others to do the same. I wonder whether a modified version of the Android OS could support RAW format…
Amobil published an article about some joint ventures between camera and phone companies [3]. Apparently LG are working on a phone with 3* Optical Zoom that uses Pentax optics, while the Olympus camera company is considering the purchase of a phone company with the apparent aim of producing a killer camera-phone.
I wonder whether I should delay the purchase of my next phone for a few months to take advantage of some of these developments. If nothing else I expect some significant improvements in the screen resolution of phones in the near future. The maximum screen resolution that is common at the moment is 800*480 (WVGA), but the iPhone 4 supports 960*640 resolution which is 60% more pixels and I expect other manufacturers to release phones to compete with it in the near future.
Election Tomorrow
On Saturday we will have a Victorian state election. As usual for state elections most people will vote on issues related to the federal government, the mainstream media has little coverage of state politics and people seem to vote on what they see on TV. Presumably that means we have a good chance of having a similar situation to the last Federal Election where the Labor and Liberal parties each won 72 seats in the lower house and Labor formed a coalition with the Greens MP and three independents.
The independent MPs didn’t give much explanation of the reasons for their choices. But it seems that a large motivating factor was the Greens success in the senate, as Labor was more willing to work with the Greens that meant that if a Liberal based coalition had won in the lower house there was a good chance of a Double Dissolution.
The Liberal party can’t make deals
In a world where sanity prevailed the result of this would be the Liberal party firstly adjusting their policies to appeal to Greens voters and secondly trying to make some deals with the Greens at a high level to allow the possibility of a Liberal/Green coalition government. While there are substantial policy conflicts between the Liberal and Green parties it does seem possible to get a coalition working if both sides accept that they won’t get everything that they want. Forming government and getting only some of your policy implemented seems like a better option than being in the opposition and getting almost none of your policy implemented. Also there is no reason why we couldn’t have a Liberal/Labor coalition government – in the next decade it seems unlikely that any election will deliver a result that doesn’t have Liberal + Labor comprising more than 50% of the seats in both houses.
But it seems that sanity doesn’t prevail. The Liberal party have put the Greens below Labor on their preferences for the upper house and on their How To Vote cards for the lower house [1]. This greatly increases the probability of Labor scoring an outright win. It also seems likely to drive a wedge against the conservative voters who want to conserve the environment.
The Sad State of the Liberal Party
Kevin Andrews (Liberal MP and former minister) wrote a strange and amusing diatribe titled “The ideological drive behind the Greens” [2]. Here is what I regard as the best part:
First, those who vote Green as their primary vote: “This is the Don’s Party group that used to be in the ALP in the ‘60s and ‘70s: young university students or graduates, frequently working or still studying in academia, no kids, often gay, arts and drama type degrees or architecture where they specialise is designing environmentally friendly suburbs, agnostic or atheist, often US or Canadian refugees from capitalism, but well paid in professional consulting or media jobs.â€
According to the CIA World Factbook [3] the median age of Australians is 37.5, the majority of the population were born in 1972 or later. The film Don's_Party was released in 1976 and was about the 1969 election. While Kevin Andrews was old enough to remember the 1969 election clearly the majority of the Australian population weren’t even born before that election and isn’t old enough to have watched the movie when it was in the cinemas. Kevin is making it quite clear that he and his party represent a time that is past. The rest of that paragraph is filled with strangeness that is a good sample of the rest of his article.
The sad thing is that he seems to think that this appeal to the minority of people who are old enough to remember the 1969 election, bigoted enough to appreciate the discrimination against homosexuals (which is a long standing Liberal policy), and politically clueless enough to support McCarthyist policies against alleged communists.
We need a decent and sane conservative party to represent the decent and sane Australian citizens who are politically conservative. I am beginning to doubt that the Liberal party could ever be reformed enough to become such a party.
Just over a month ago I bought a Wikireader [1] from Officeworks (an Australian chain of stores that sell all manner of office supplies). It cost only $99, thanks to Brianna for informing me about this [2]. When I purchased my Wikireader an Officeworks employee had to get one from the back office and told me that I was the first person to buy one. I suggested to him that when a product isn’t mentioned in their advertising and isn’t put on the shelves it’s unlikely to sell in quantity and that they shouldn’t rely on bloggers to promote what is possibly one of the most desirable products that they stock.
The Wikireader stores a copy of the text of the English language version of Wikipedia on a micro-SD card. They have a service whereby you can get two updates posted to you every year for $29, which would make it pretty close to free once postage and the cost of the micro-SD cards is taken into account. Also you can download new content. I have no immediate plans for updating my Wikireader as the content is more than good enough to answer idle questions while waiting for a bus but as it’s lacking external links due to no net access and images it can’t be used for serious Wiki reading IMHO.
Brianna has documented the process of updating a Wikireader to add more content [3], she added the Chinese version and discovered that inter-wiki links are preserved! I have no immediate plans to add extra content (I don’t know any other language well enough to read an encyclopaedia). Also an 8GB MicroSD card (which is the minimum requirement to use multiple languages) costs $35 and is a significant portion of the original purchase price.
In terms of functionality the device is pretty good. The screen is not back-lit, but if it was then the two AA batteries wouldn’t last anywhere near a year. The screen is not high resolution and the touch functionality isn’t particularly accurate or sensitive – but I guess that’s a necessary trade-off to get the $99 price. The Wikipedia content seems quite complete, so far the only page which I found to be missing was the bio of an Australian architect, I’m not sure if his page was removed from the Wikireader to save space or whether my device has a snapshot that predates the addition of the page.
The Wikipedia page about downloading the database is interesting [4], it’s 6GB of compressed data for the text of the English pages (not including history or talk pages) and for years they haven’t even tried to provide a dump of the images. So I guess that a Wikireader that displays pictures is out of the question.
The Wikireader has a parental filter, in my quick tests the only page that has been blocked is “Sexual Intercourse“, I could read all about safe-sex, infidelity, and lots of other related “adult” topics without being asked for a password. It also shows pages about “goatse” and other related things without asking for a password – NB if you don’t know what “goatse” is then you probably don’t want to learn, trust me that it’s something that most people won’t want their children to learn about. The filter is so bad that I think they shouldn’t include it, it will just give people false confidence. It’s OK to sell a cheap device that is designed to give a detailed description of goatse etc on request to anyone, but IMHO it’s not OK to sell such a device with a claim that it is “kid safe” and has “parental controls“. Note that holding down the History button will allow you to clear your history – this is useful if you have just verified that goatse isn’t blocked and you want to give the device to a young child.
There is a button to give a random page, I believe that this would be more useful if it had some metric to make it more often return pages that might be interesting. It could weight the randomness by the length of the page (usually a longer page is more interesting to more people and has more links to other pages) or by some other metric that indicates the potential popularity. Random links often get me pages about obscure country towns and other things that probably aren’t of interest to people who don’t live near them.
But overall this is a great product, $99 is not much to pay, and I recommend getting one!
Guy Deutscher wrote an interesting article for the New York Times about how language shapes how we think [1]. The example of people who have no language construct for self-sentered directions and how they describe things is particularly interesting.
TED published an interesting interview with Shaffi Mather – the founder of India’s first organised ambulance service (with differential pricing based on ability to pay) [2]. He also talks about founding schools in small towns and his BribeBusters.com company.
World Changing has an interesting article about a legislative change in California that allows car-sharing of personal vehicles [3]. The concept is that if you own a car that you don’t use most of the time (as is usually the case) then you can contract with a car-share company to share it to others when you don’t need it. This saves the car share company from the capital expense of owning cars and thus allows them to place cars in remote locations that wouldn’t otherwise be financially viable (IE the street in front of random people who sign up). The person who owns the car may get about $2 per hour for the time when it’s rented. The car owner gets to specify when the car may be available.
Charles Stross wrote an entertaining and informative rant about Steam-Punk [4]. He cites Michael Moorcock’s informative essay about Starship Troopers and other right-wing apologist themes in sci-fi [5] as well as China Mieville’s essay about politics and The Lord of the Rings [6].
Glenn Greenwald wrote an informative article about the New York Times defending torture by the US military [7]. I have unsubscrubed from the @Times mailout and will avoid citing NYT articles wherever possible. I sent the URL for Glenn’s article to the NYT feedback address but I don’t expect them to take any notice.
Fate Of the World is a new computer game that’s in beta where you have a simulation of the next 200 years of climate change [8]. It’s currently in beta for Windows only, they hope to have a Mac version in March and have no stated plans for Linux support.
Cory Doctorow wrote an interesting article for Locus about Sci-Fi fans and cosmopolitanism – taking the best option after consideration rather than doing what’s locally fashionable [9]. He uses the term “Martian” to refer to some of the viewpoints, but it seems to me that “Vulcan” would be more appropriate.
The Wall St Journal has an interesting article about people who manufacture drugs that aren’t yet illegal, every time one drug gets banned they market a new one [10]. This is yet another example of the “War on Drugs” doing more harm than good, instead of taking drugs which have well known effects (that can be treated by hospitals) people are taking weird new drugs and no-one knows what will happen to them.
Mieke Meijer in the Netherlands has invented a new product known as “newspaper wood” [11], it involves gluing paper together to create a form of chip-board that keeps the layers of paper distinct to give a result like wood grain. The World Changing commentary suggests that this could give a “heirloom quality” to objects made with it, while I’m dubious about that I think that the surface would be pleasing to look at in a kitchen or office environment.
Ze Frank gave an interesting TED talk about unusual social projects that he’s run on the Internet [12]. This includes an attempt to reconcile Red and Blue voters after the 2008 US presidential election, the creation of inspirational songs, and remixing the “Whip Somebody’s Ass” song. This is really worth watching!
The Chronicle Review has an interesting article by someone who is paid to complete academic assignments for other people [13]. The scope of cheating that is claimed is profound. Naturally we have to take claims by someone who admits acting unethically with a grain of salt, but if there is any truth to this then it’s a serious matter. I’m surprised that no-one has made a serious attempt to catch the customers of such people.
David Brin (the famous sci-fi author) gave an interesting short lecture about the future of humanity [14]. He promotes the Lifeboat Foundation (of which he is a director) and describes his concern about the Fermi Paradox.
Shimon Schocken gave an inspiring TED talk about his work rehabilitating juvenile prisoners through taking them mountain-bike riding [15]. This shows that anyone can do great things to help other people, he got this idea when riding past a prison, convinced the prison governor that it was a good idea and then started doing it.
Conrad Wolfram gave an insightful TED talk about math education [16]. His claim is that the entire mathematical education system is wrong in it’s focus on hand calculation, instead the aim should be to teach children how to use computers to solve problems – which is what is mostly done in the real world.
I’ve just been asked for advice on buying a digital camera. I’m not an expert on cameras but I have a good general knowledge of technology – and I’m sure that the readers of my blog will correct me rapidly if I make any serious mistakes. ;)
Types of Camera
The Wikipedia Page about Digital Cameras is worth reading [1].
Here are the types of camera that are useful as a stand-alone camera (IE not camera phones or industrial cameras):
- Digital SLR – large, very capable, and very expensive. They have detachable lenses and a prism to split the light between a viewfinder and the CCD that records the digital photo. Such a split provides much less benefit now that you can have an LCD display for the viewfinder. In Australia they seem to start at about $1500.
- Bridge Cameras – they are of a similar size and shape to a Digital SLR, but the lens is permanently attached and the price is a lot lower. Typically between $400 and $800.
- Mirrorless Interchangeable Lens Cameras – they allow changing lenses like a DSLR but don’t have the prism for an optical viewfinder. This makes the optics simpler and cheaper. Andre Pang wrote a good review of one [2] – which sells for about $700.
- Compact cameras – small and cheap. Between $60 and $400 depending on features.
I suggest that people not start out a hobby of digital photography with a DSLR or other interchangeable lens camera. I think that it’s best to start out with simple gear that’s cheap – if you decide that digital photography is not your thing then you have wasted less money, and if you really get into it then you’ll be able to make a more informed choice about an expensive camera after getting some experience.
A spare cheap compact camera can be useful even if you own a more expensive camera. There are times when you don’t want the bulk of a DSLR or Bridge Camera and when you have a risk of theft or accidental damage such that you don’t want to take an expensive camera. People who are really serious about photography apparently take a camera everywhere, you could have a compact camera in your front pocket for fast pictures and a bulky camera in your backpack for when you have time to prepare a quality shot. So buying a cheap camera and then buying an expensive one a few months later would not be wasting money!
As the person who asked for advice has never owned a digital camera before I’ll focus on cheap compact cameras for the rest of this post.
Pixels and Lenses
Cameras are typically advertised with the resolution in Megapixels described in bold. Presumably most people search for the camera with the highest resolution. The first thing to beware of is cameras that don’t have hardware which is capable of taking a picture of the stated resolution, they use interpolation to generate a higher resolution image. There are probably some cameras with interpolation that are OK and provide a decent picture at a low price, but generally I recommend avoiding all cameras that do interpolation.
Optical zoom is a very important feature. Often pictures have to be cropped to remove unwanted background, if you zoom in appropriately you can avoid cropping and make better use of the available resolution. Beware of cameras that advertise things such as “advanced zoom“, anything that doesn’t exactly say “optical zoom” is using digital zoom – IE interpolation. I suggest not considering a compact camera unless it can do at least 4* optical zoom, with 5* or better being preferable.
The physical size of the lens is important. A bigger lens allows better pictures in adverse lighting and also allows a faster shutter speed to give better photos of moving objects and better photos when you are moving. Generally you can get a rough idea of the potential that a camera has by just glancing at the lens, if it’s the size of a lens in a mobile phone then the pictures won’t be that great. If it is on a telescopic mount and it’s wide then the result will be better. When buying a lens for a DSLR or other detachable lens camera you should be able to read specifications of the lens which indicate it’s size. For compact cameras the specifications of the lens are usually available from the vendor and often available from review sites but generally aren’t included in adverts by retailers. If you are comparing cameras in the store looking at them seems like the best option.
The ratio of the lens area to the number of pixels determines how much light is received by the sensors for each pixel. So when there are two cameras that are essentially identical apart from the number of megapixels the one with the highest number isn’t necessarily better in all situations. A 12MP camera might not give a better result than a 10MP camera, a monitor described as “Full HD” has a resolution of 1920*1080 which is 2MP. A 5MP camera is useful to allow cropping but if the aim is to display pictures on current monitors then anything much bigger than 5MP is probably wasted at this time and 10MP will provide pictures that can use the capabilities of monitors that are developed for a while.
Printing
Some printers that are affordable for home use might require something like a 7MP camera to print a picture at A4 or Letter size at the highest quality. Professional printing will probably require something even greater. But if your intended use of a digital camera doesn’t involve printing the pictures, or only rarely involves printing them at A4 or Letter size then you don’t need a high resolution for printing. I expect that there are some available printers that can use paper at sizes such as B3 which might require a 20MP camera for best quality. But if the aim of the printing is to put a picture on your wall (the most common case) then even if it’s not at the ideal resolution then probably no-one will notice the difference – you can’t see the pixels from a few meters away.
If the aim of the camera is to photograph professional artwork for the purpose of selling it on the Internet then a high resolution camera really isn’t desired. You want to offer pictures on the Internet which aren’t good enough to be usefully printed.
Video
The capabilities for recording video can vary significantly between different cameras in the same range. If you don’t care about video then that’s fine, but if video matters to you then you have to read the specs. It’s also worth considering digital video cameras, I have previously summarised the available digital video cameras – although I’m sure that there have been some new models since then [3]. A good (expensive) digital camera will have video functionality that compares well to most digital video cameras – but it will cost a lot more.
Choosing a Compact Camera
There are many compact cameras in the $100 to $150 price range. Ted’s has the Samsung Digimax ES65 for $99.95 which has 10MP and 5* optical zoom. This seems like a good deal. Practice with a cheap camera could easily allow you to make a better choice when buying a more expensive camera that saves you more than $100 so it seems unlikely that you will have any great regrets about buying a $100 camera.
Buying from the specs is a bad idea, I recommend testing a camera in the store before buying – every store that you want to buy from allows this. But don’t expect that quality pictures in the store means much, the people who run the camera stores usually set them up with good lighting so that pictures will tend to turn out well. The aim of an in-store test is not to discover what the camera does well, but to discover what (if anything) it does badly. Also it’s useful to test the ergonomics of the camera before buying, discover whether you would be happy to hold the camera for an hour.
It’s a good idea to ask the staff at a camera store for advice, but don’t rely on such advice. My experience is that they tend not to ask what the prospective customer plans to do with the camera and this significantly limits the quality of their recommendations.
Conclusion
Make your first digital camera a cheap compact camera that doesn’t cost much more than $100. Make sure it has at least 4* optical zoom with 5* being preferred. Don’t worry too much about the number of megapixels, anything more than 5 will do. Test the camera in the store to look for any obvious reasons that make it unsuitable for your use. If you want video then be prepared to pay a little more as the cheapest cameras have a low resolution for video.
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